libjava/gnu/classpath/jdwp/util/Signature.java

   1 /* Signature.java -- utility class to compute class and method signatures
   2    Copyright (C) 2005 Free Software Foundation
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 terms of your choice, provided that you also meet, for each linked
  32 independent module, the terms and conditions of the license of that
  33 module.  An independent module is a module which is not derived from
  34 or based on this library.  If you modify this library, you may extend
  35 this exception to your version of the library, but you are not
  36 obligated to do so.  If you do not wish to do so, delete this
  37 exception statement from your version. */
  38
  39
  40 package gnu.classpath.jdwp.util;
  41
  42 import java.lang.reflect.Method;
  43
  44 /**
  45  * A class to compute class and method signatures.
  46  *
  47  * @author Tom Tromey  (tromey@redhat.com)
  48  * @author Keith Seitz  (keiths@redhat.com)
  49  */
  50 public class Signature
  51 {
  52   /**
  53    * Computes the class signature, i.e., java.lang.String.class
  54    * returns "Ljava/lang/String;".
  55    *
  56    * @param theClass  the class for which to compute the signature
  57    * @return          the class's type signature
  58    */
  59   public static String computeClassSignature (Class theClass)
  60   {
  61     StringBuffer sb = new StringBuffer ();
  62     _addToSignature (sb, theClass);
  63     return sb.toString ();
  64   }
  65
  66   /**
  67    * Computes the method signature, i.e., java.lang.String.split (String, int)
  68    * returns "(Ljava/lang/String;I)[Ljava/lang/String;"
  69    *
  70    * @param method  the method for which to compute the signature
  71    * @return        the method's type signature
  72    */
  73   public static String computeMethodSignature (Method method)
  74   {
  75     return _computeSignature (method.getReturnType (),
  76                               method.getParameterTypes ());
  77   }
  78
  79   private static String _computeSignature (Class returnType,
  80                                            Class[] paramTypes)
  81   {
  82     StringBuffer sb = new StringBuffer ("(");
  83     if (paramTypes != null)
  84       {
  85         for (int i = 0; i < paramTypes.length; ++i)
  86           _addToSignature (sb, paramTypes[i]);
  87       }
  88     sb.append (")");
  89     _addToSignature (sb, returnType);
  90     return sb.toString();
  91   }
  92
  93   private static void _addToSignature (StringBuffer sb, Class k)
  94   {
  95     // For some reason there's no easy way to get the signature of a
  96     // class.
  97     if (k.isPrimitive ())
  98       {
  99         if (k == void.class)
 100           sb.append('V');
 101         else if (k == boolean.class)
 102           sb.append('Z');
 103         else if (k == byte.class)
 104           sb.append('B');
 105         else if (k == char.class)
 106           sb.append('C');
 107         else if (k == short.class)
 108           sb.append('S');
 109         else if (k == int.class)
 110           sb.append('I');
 111         else if (k == float.class)
 112           sb.append('F');
 113         else if (k == double.class)
 114           sb.append('D');
 115         else if (k == long.class)
 116           sb.append('J');
 117         return;
 118       }
 119
 120     String name = k.getName ();
 121     int len = name.length ();
 122     sb.ensureCapacity (len);
 123     if (! k.isArray ())
 124       sb.append('L');
 125     for (int i = 0; i < len; ++i)
 126       {
 127         char c = name.charAt (i);
 128         if (c == '.')
 129           c = '/';
 130         sb.append (c);
 131       }
 132     if (! k.isArray ())
 133       sb.append(';');
 134   }
 135 }